Compressing tool with release means for the full stroke compelling mechanism



Nov. 15, 1960 L. FREIMARK 2,959,993

coMPEEssING TooL WITH RELEASE MEANS Foa TEE FULL STROKE coMPELLING MECHANISM Filed July l, 1959 IN V EN TOR.

United COMPRESSING TOOL WITH RELEASE MEANS FOR THE FULL STRGKE CUMPELLING MECH- NISM Leo Freimark, Flushing, NX., assigner to Vibro Manufacturing Co. luc., Woodside, N.Y.

Filed July 1, 1959, Ser. No. 824,361

3 Claims. (Cl. 81-15) The present invention refers to tools belonging to general category of pliers, and more specically to compressing tools, particularly for crimping and similar operations.

In the case of crimping tools used for crimping a tubular connecting element around one or more wires it is desirable to assure satisfactory crimping by providing the tool with iocking means preventing an inadvertent discontinuation of the crimping operation before completion of a full stroke of the crimping jaws, i.e. a reversal of the closing movement of the jaws unless they have been moved to a predetermined substantially closed relative position. Tools of this kind are known. However, it may happen that the operator discovers during the course of the operation, i.e. while the handle levers of the tool are being moved from their fully open position toward their closed position, that e.g. a wire or the connecting element is mislocated or damaged so that completion of the crimping operation beyond an intermediate relative position of Athe jaws is either undesirable or even impossible. ln such cases considerable ydiiiiculty is encounteredN because now in conventional crimping tools of the type mentioned the locking means would make it impossible to reverse the movement of the handle levers and to open the jaws.

It is, therefore, a main object of Ithis invention to provide for tools of the type set forth releasing means permitting in ease of need an elimination of the locking effect of the locking means.

It is a further object of the invention to provide releasing means of said type which are of simple construction and reliable in operation.

With these objects in mind, a compressing tool having a pair of cooperating pressure jaws, particularly for crimping and similar operations, comprises, according to the invention, in combination, two pivotally jointed handle levers operatively connected with said pair of jaws, respectively, and being movable between a relative position associated with an open condition of said pair of jaws, and a second position associated with a Vpredetermined substantially closed condition of said pair of jaws; locking means interposed between Said two handle levers and so constructed that after said levers have been moved from said first position toward said second position, a reverse movement towards said iirst position is prevented unless said levers have reached said second position corresponding to said predetermined substantially closed condition of said pair of jaws; and release means associated with said locking means for temporarily eliminating the locking eifect thereof whenever a movement of said levers to said second position is impossible or undesirable.

A preferred embodiment of the invention will be described in conjunction with the accompanying drawing. It is to be understood, however, that this invention is susceptible of various modifications within the scope of the appended claims.

Patented Nov. 15, 1960 In the drawing:

Figs. l and 2 illustrate a tool of the type set forth, in its iirst and second positions, respectively, the release means being omitted for the sake of clarity;

Figs. 3 and 4 show, at large scale, the locking means' thereof;

Fig. 5 illustrates, at still larger scale, release means in combination with locking means as shown by Figs. 1 4; and

Fig. 6 illustrates isometrically a release member according to the invention. p

Basically, the tool shown by Figs. 1 and 2 comprises a pair of handle levers 1 and 2 connected, respectively with pressure jaws 3 and 4, each having a crimping portion 5 recessed from the face of the pertaining jaw and designed to be forced into a connector sleeve 6 surrounding two wires '7. Fig. l shows the tool in position `during the opening stroke still before being fully ready to accept the connection to be crimped, while Fig. 2 shows the same tool in fully closed position in which the jaws 3 and 4 are in a predetermined substantially closed condition as required for satisfactory crimping.

The levers 1, 2 are pivotally jointed by a pivot pin 8. A brace member 9 is hingedly connected at 10 to the lever 1, while its free end is slidingly accommodated in a lock member 11 hingedly connected at 12 to the other lever 2. A portion of the brace 9 is provided with a series of teeth 13 acting as a ratchet but being preferably 'formed symmetrical. The series of teeth 13 may extend to the free end of the brace 9 or may end a certain distance therefrom, a straight portion 14, substantially in line with the roots of the teeth 13 being left. Similarly, a recess 15 having its bottom surface also substantially in line with the roots of the teeth 13 is provided adjacent to the opposite end of the series of teeth 13.

The lock member 11 is formed as a iiat sleeve or box with open ends so that the brace may slidably move through it in its longitudinal direction. It can be seen, that when the tool is opened by moving Ithe levers 1 and 2 apart in the direction of the arrows A in Fig. l, the brace 9 will move, relatively to the lock member 11, in direction of arrow B. When the tool is closed to the position of Fig. 2, the brace 9 moves in the opposite direction. Y

The lock member 11 comprises a pawl member 16 turnably held by a pivot 17. The pawl 16 has a projecting locking arm 18 adapted to engage the opposite teeth 13 as will be explained below. A spring 19 is attached at 20 to the pawl 16 and at 21 to a pin 22 so that it tends to turn the pawl from any angularly displaced, position to its normal position shown in Figs.v 2 and 3.

Assuming the tool has been brought to its closed position as shown by Fig. 2, then the relative position of pawl 16 with respect to the brace 9 and particularly to the teeth 13 will be as shown by Fig. 3. The recess 15V is so located along the brace 9 that in the fully closed position of the tool (complete crimping) the pawl can be held by spring 19 in normal position as shown. When then by moving the levers 1, 2 in direction of arrows A the brace 9 is moved out of the lock member 11 in direction of arrow B (Figs. l and 3) the starting tooth 13 will tilt the pawl 16 into the position shown in Fig. Vl, against the action of spring 19. The movement of the brace 9 is in 5 no way hampered thereby. However, it can be seen that 2 toward each other in direction opposite to arrows A which causes the brace 9 to move through the lock member 11 in direction of arrow C in Figs. 3 and 4. In this case the pawl 16 is tilted in oppbsitedirection by .the .last one of the teeth series 13. This movement is not hampered by .the pawl 16, but it can be seen again that this movement cannot be reversed unless the pawl 16 has passed completely the Vteeth series 13 and is free to tilt back into normal position under the action of spring 19 as shown by Figs, 2 and 3, the latter indicating that this condition is only met when the jaws 3, 4 are `in their predetermined substantially closed position because the recess is located inl accordance with this condition. 1

In order Vto b e able 'to release the pawl 16 from its locking position existing` ,during the entire closing movement of the tool as shown by Fig. 4, release means are provided according to the Linvention as illustrated by Figs. 5 and 6,. The releasing means, in this preferred embodiment, consists of two parts only, namely a release sleeve 23and a spring24. The sleeve 23 is formed from sheet metal to a box-like shaped body 23 the cross-section of which corresponds to that of the sleeve portion 11 of the ylock member 11, sliding on the brace 9. The latter being preferably a square rod, the sleeve portion 11' and the body 23 are shaped accordingly, so that the sleeve 11 embraces the brace 9, and the body 2 3' embraces slidably the sleeve 11', without either having the possibility of turning around the brace 9. The body 23' has at one end, ush with its bottom wall, a projecting tongue 23". When the release means is assembled with the lock member 11 and brace 9 as shown in Fig. 5, the tongue 23 extends along the lower side of the brace 9, i.e Valong the side having the teeth 13. In transverse dire'ction'the body 23 is provided adjacent to theend from which the tongue 23" projects, with laterally `projecting flaps 23a for facilitating its operation that will lbe described below` 'Ther spring 24 is interposed between the just mentioned end of thebody23 and the opposite wall portion of the lock member 11. This spring is likewise preferably formed so that it embraces the portion 11', i.e. with a substantial-ly square inner cross section and made up from flat vstrip material, consequently the spring 24 is likewise prevented from turning although this is not critical.y In normal, i.e. comparatively relaxed condition the spring 24 urges the sleeve member'23 into its normal position shown in Fig. 5. For predetermining this normal orL idleposition, a tit` 236 is extruded from the tongue 23" upwardly towardthe brace 9 so that this tit 23b will abut against the inner end 11 of the sleeve portion 11' thus limiting the outward movement of the sleeve 23.

In its normal position the free end of the tongue 23" does not interfere with the pawld, more specifically with the engaging arm 18 thereof, in any one of its normal or tilted positions. However, when the pawl 16 is, during the closing movement of the tool, in the position of fFig. 5 the pawl 16 may be released easily from the engagement of its arm 18 with the teeth 13 by pushing the sleeve 23 manually, against the action of spring 24, in direction of arrow D until the free end of the tongue 23 abuts against the flank of the arm 18 and thereby forces Ithe latter out of engagement with the teeth 13. Thus the tool may be opened although the predetermined fullyclosed condition has not been reached yet. Upon release the sleeve 2,3 returns toits normal position due to the action of spring 24.

The spacing between consecutive turns of the spring 24 may be chosen so that complete closing of these turns constitutes a desirable limitation of the inward stroke of the tongue 23" so that undue jamming of the pawl 16 is prevented which might occur if the free end of the tongue 23" were to overrun the edge of the arm 18.

I-t can be seen that the release means according toy the invention is extremely simple in construction, reliable in operation and in no way hampers the normal operation of the tool nor makes it bulky or unwieldy.

It should be understood that the invention is not intended to be limited to the details of the preferred embodiment described and shown since modifications thereof may be introduced by those skilled in the art without departing from the scopeY and `gist of the invention.

What I claim is:

1. In a compressing tool having a pair of cooperating pressure jaws, particularly for crimping and similar operations, in combination, two pivotally jointed handle levers operatively connected with said jaws, respectively, and movable between a rst relative position associated with an open condition of said pair of jaws, and a second relative position associated with a predetermined substantially closed condition of said pair of jaws; locking means interposed between said two handle levers and comprising a brace member hingedly connected to one of said levers, and a cooperating lock` member hingedly connected to the other one of said levers, ratchet and pawl means engageably interposed between said brace and lock members and permitting relative movement 4therebetween in both longitudinal directions of said brace member, but preventing a reversal of said movement unless said ratchet and pawl members are out of engagement with each other; and release means associated with said locking means and comprising a release member slidably mounted on said brace member adjacent to said lock member for movement in llongitudinal direction of said brace member between a normal position and an operative position, and spring means for urging said release member toward its normal position, said release member Abeing provided with an operating portion capable of engaging said pawl means when said release member -is moved into its operative position for engaging said `pawl means so as to cause its disengagement from said ratchet means.

2. A compressing tool as claimed 'in claim l, wherein said sleeve member and said sleeve portion are provided with cooperating stop means -for limiting the movement of said sleeve member from its operative position to its normal position.

3. A compressing tool as claimed in claim 2, wherein said spring means urging said release member toward its normal position is provided with a plurality of turns spaced from each other in such a manner that complete closing of said turns limits the movement of said sleeve member to its operative position which is determined thereby.

References Cited in the file of this patent 

